Classe Audio CDP-88, Owner'S Manual

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barely be detected. The crystal oscillator itself is designed to generate a spectacularly low jitter of
approximately 2 picoseconds!
There is a single AES/EBU balanced digital output on an XLR 3-pin Neutrik connector. A final
technical highlight of the CDP-88 is the custom remote handset. It features an exceptionally wide
transmission angle to the IR receiver on the CDP-88, and is engineered to last an extremely long time.
The CDP-88 features an HDCD decoder that, in addition to allowing full HDCD decoding,
functions as a state of the art 8X oversampling filter if the input data is not encoded in HDCD format.
The CDP-88 employs a high performance 20-bit digital-to-analog converter, which serves to decode
both left and right channel information. The digital information is oversampled by the HDCD decoder to
a rate that is 8 times higher than the original sampling frequency. Oversampling the digital data to such
a high rate allows the analog filter following the DAC to have far fewer poles than would be otherwise
required. This allows a simpler analog filter to follow the DAC which reduces the errors that are
associated with “brick wall” analog filters, and also minimizes the number of components in the signal
path. With non-HDCD encoded data, the decoder exhibits performance to common digital filter IC’s.
The stop band attenuation is greater than -120dB, and the internal calculations are carried out with 27-bit
accuracy. If the data is encoded in HDCD encoded format, the filter will detect it and decode it,
extracting all of the additional information available with an HDCD recording. The HDCD indicator on
the front panel will dome on if the HDCD encoded data is detected. The indicator will be off for a
normally encoded CD. The analog gain is increased by 6dB automatically when an HDCD disc is
detected, as suggested by Pacific Microsonics, Inc. The HDCD filter also performs de-emphasis
filtering for discs encoded with preemphasis.
The output of the UltraAnalog, Inc 20-bit dual DAC is followed by passive 3-pole, linear phase,
anti-imaging filters to remove any artifacts beyond the audio frequency range from the analog audio
signal. Tight tolerance, low temperature coefficient polypropylene capacitors and 1% metal film
resistors are used in the filter for long term accuracy and stability. The last stage of the filter is a passive
6dB attenuator to provide the proper HDCD levels.